Active duty
Active duty, in contrast to reserve duty, is a full-time occupation as part of a military force.
Indian
The Indian Armed Forces are considered to be one of the largest active service forces in the world, with almost 1.42 million active-duty personnel. An additional 2.20 million reserve forces can be activated in a few weeks, depending on the situation, under the order of the president of India who is the commander-in-chief of the armed forces of India. This does not include the additional 1 million troops of the paramilitary, which is also an active force whose full-time responsibility is to guard the sovereignty of the nation from internal and external threats.Israel
In the Israel Defense Forces, there are two types of active duty: regular service, and active reserve duty. Regular service refers to either mandatory service, according to the laws of Israel, or standing army service, which consists of paid NCOs and officers.Active reserve service refers to the actual time in which reservists are called up. This varies from once every few years to a month every year. During active reserve duty, military law can be applied to reservists, similarly to regular soldiers.
Pakistan
The Pakistan Armed Forces are one of the largest active service forces in the world, with almost 654,000 full-time personnel, due to the complex and volatile nature of Pakistan's relationship with India and the Kashmir region, and its porous border with Afghanistan. An additional 550,000 part-time reservists can be activated in weeks depending on the situation, by order of the President of Pakistan who is the Commander and Chief of the Armed Forces of Pakistan. This does not include the additional 385,000 troops of the Civil Armed Forces who are also active forces whose full-time responsibility is to guard the external borders.United Kingdom
In the United Kingdom and the Commonwealth the equivalent term is active service. The term "colour service" has been traditionally used to distinguish time spent on active service, versus reserve service.From the end of the Napoleonic Wars until 1847, men were enlisted for twenty-one years, practically for life. Thereafter, the term of enlistment was ten years, then twelve years. On completion of their enlistment, soldiers had the choice between accepting discharge without pension or to extend so as to accumulate 21 years of service. After many years with no trade other than that of soldiering, more than half of all discharged soldiers chose to re-enlist immediately. Of those who took a voluntary discharge, fully one in five signed on again within six months.
Cardwell therefore brought before Parliament the idea of "short service". The act of 1870 allowed a soldier to choose to spend time in the reserves after service with the colours. As to the proportion of time spent on active service with the colours versus the balance in the reserve, this was to be laid down from time to time by the Secretary of State for War. Among the other benefits, this thereby enabled the British Army to have a ready pool of recently-trained men to draw upon in an emergency.
In 1881, under the Childers Reforms short service was increased to seven years with the colours, and five with the reserve, of the twelve-year enlistment period that the Cardwell Reforms had introduced.
In 1914, at the outbreak of war, forty percent of the infantry were on active service, the remaining sixty percent of the infantry consisted of men recalled from the reserve.
At present, the minimum length of active service is four years, if over 18 years upon enlisting. For those enlisting who are under 18 years, they are obliged to serve at least until their 22nd birthday. Prior to 1999, the minimum length had been three years. Upon leaving full time service, personnel are transferred into the reserves which usually lasts for six years.